Benchmarking of commercial EUVL resists at SEMATECH

Abstract

Extreme ultraviolet lithography (EUVL) is one of the leading candidates for next-generation lithography technology for the 32 nm half-pitch node and beyond. The availability of EUV resists is one of the most significant challenges facing its commercialization. A successful commercial EUV resist must simultaneously meet resolution, line width roughness (LWR), photosensitivity, and resist outgassing specifications. Photosensitivity is of particular concern because it couples directly to source power requirements and the source is widely viewed as the most daunting challenge facing EUV commercialization. To accelerate EUV resist development, SEMATECH has two programs that provide the resist community access to EUV exposure capability: 1) the EUV Resist Test Center (RTC) at SEMATECH at Albany, SUNY, and 2) the SEMATECH microexposure tool (MET) at Lawrence Berkeley National Laboratory. SEMATECH uses both facilities to benchmark EUV resists in close cooperation with resist suppliers. Here we summarize results from the SEMATECH EUV resist benchmarking project including process windows, exposure latitude, and depth of focus, photospeed, LWR, and ultimate resolution. Results show that EUV resists meet resolution and outgassing requirements for the 32nm half-pitch node. LWR and photospeed, however, remain a concern especially for contact-hole printing. Moreover, progress towards the 22nm half-pitch node has also been demonstrated in terms of resolvability.